What Are Lice?

Head Lice (pediculus humanus capitis) is one of the most common human parasitic infestations worldwide. In the United States, an estimated 6-12 million people are treated for head lice each year, and studies have shown that it’s most common among preschool and school-aged children.

Head lice can infest anyone’s hair, regardless of gender, nationality, race, or hygiene. Even the cleanest classrooms and tidiest households can be invaded by this common nuisance. They can’t fly or jump. The most common way they spread is through direct head-to-head contact with an infested person

Head lice are very small — about the size of a sesame seed. They can be tan, brown, or gray in color. This parasite prefers a dark, warm environment and is often discovered behind the ears, under a ponytail and at the nape of the neck.

Head lice are parasitic insects that only attack humans. You won’t catch lice from the family pet, nor will you give lice to them.

Head lice stay alive by feeding on blood from the human scalp. They will die within 1 to 2 days after being off their host because they no longer have a food source.

A female louse can lay up to 10 eggs daily; they prefer to lay their eggs ¼” from the scalp.

At first glance, head lice eggs (or nits) might be mistaken for dandruff. But they are firmly attached to the hair shaft with a waterproof glue-like substance and won’t brush off.